Problem 46057. Find the last non-zero digit in a primorial

Created by ChrisR

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{"parts":[{"partUri":"/matlab/document.xml","contentType":"application/vnd.mathworks.matlab.code.document+xml","content":"<?xml version=\"1.0\" encoding=\"UTF-8\"?><w:document xmlns:w=\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\"><w:body><w:p><w:pPr><w:pStyle w:val=\"text\"/><w:jc w:val=\"left\"/></w:pPr><w:hyperlink w:docLocation=\"https://www.mathworks.com/matlabcentral/cody/groups/2001/problems/45251\"><w:r><w:t>Cody Problem 45251</w:t></w:r></w:hyperlink><w:r><w:t> asked us to find the last non-zero digit in a factorial. For this problem consider the primorial </w:t></w:r><w:customXml w:element=\"equation\"><w:customXmlPr><w:attr w:name=\"displayStyle\" w:val=\"false\"/><w:attr w:name=\"altTextString\" w:val=\"p_n\"/></w:customXmlPr><w:r><w:t>p_n</w:t></w:r></w:customXml><w:r><w:t>#, the product of primes up to and including the </w:t></w:r><w:customXml w:element=\"equation\"><w:customXmlPr><w:attr w:name=\"displayStyle\" w:val=\"false\"/><w:attr w:name=\"altTextString\" w:val=\"n\"/></w:customXmlPr><w:r><w:t>n</w:t></w:r></w:customXml><w:r><w:t>th prime </w:t></w:r><w:customXml w:element=\"equation\"><w:customXmlPr><w:attr w:name=\"displayStyle\" w:val=\"false\"/><w:attr w:name=\"altTextString\" w:val=\"p_n\"/></w:customXmlPr><w:r><w:t>p_n</w:t></w:r></w:customXml><w:r><w:t>. For example, for </w:t></w:r><w:customXml w:element=\"equation\"><w:customXmlPr><w:attr w:name=\"displayStyle\" w:val=\"false\"/><w:attr w:name=\"altTextString\" w:val=\"n\"/></w:customXmlPr><w:r><w:t>n</w:t></w:r></w:customXml><w:r><w:t> = 12, the primorial is 7420738134810, whose last non-zero digit is 1.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/><w:jc w:val=\"left\"/></w:pPr><w:r><w:t>Find the last non-zero digit in the primorial </w:t></w:r><w:customXml w:element=\"equation\"><w:customXmlPr><w:attr w:name=\"displayStyle\" w:val=\"false\"/><w:attr w:name=\"altTextString\" w:val=\"p_n\"/></w:customXmlPr><w:r><w:t>p_n</w:t></w:r></w:customXml><w:r><w:t>#.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/><w:jc w:val=\"left\"/></w:pPr><w:r><w:t>See also</w:t></w:r><w:r><w:t> </w:t></w:r><w:hyperlink w:docLocation=\"https://www.mathworks.com/matlabcentral/cody/problems/46054-count-trailing-zeros-in-a-primorial\"><w:r><w:t>Cody Problems 46054</w:t></w:r></w:hyperlink><w:r><w:t> \"Count trailing zeros in a primorial\" and </w:t></w:r><w:hyperlink w:docLocation=\"https://www.mathworks.com/matlabcentral/cody/problems/46060-identify-primorial-primes\"><w:r><w:t>46060 \"Identify primorial primes\"</w:t></w:r></w:hyperlink><w:r><w:t>.</w:t></w:r></w:p></w:body></w:document>","relationship":null}],"relationships":[{"relationshipType":"http://schemas.mathworks.com/matlab/code/2013/relationships/document","target":"/matlab/document.xml","relationshipId":"rId1"}]}

<div style = "text-align: start; line-height: 20.4333px; min-height: 0px; white-space: normal; color: rgb(0, 0, 0); font-family: Menlo, Monaco, Consolas, monospace; font-style: normal; font-size: 14px; font-weight: 400; text-decoration: rgb(0, 0, 0); white-space: normal; "><div style="block-size: 123.75px; display: block; min-width: 0px; padding-block-start: 0px; padding-top: 0px; perspective-origin: 407px 61.8833px; transform-origin: 407px 61.8833px; vertical-align: baseline; "><div style="block-size: 63.5px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 31.75px; text-align: left; transform-origin: 384px 31.75px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; "><a target='_blank' href = "https://www.mathworks.com/matlabcentral/cody/groups/2001/problems/45251">Cody Problem 45251</a><span style="block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 284.733px 7.91667px; transform-origin: 284.733px 7.91667px; unicode-bidi: normal; "> asked us to find the last non-zero digit in a factorial. For this problem consider the primorial <img src="data:image/png;base64,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" alt="p_n" style="width: 15.5px; height: 20px;" width="15.5" height="20"><span style="block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 19.45px 7.91667px; transform-origin: 19.45px 7.91667px; unicode-bidi: normal; ">#, the product of primes up to and including the n<span style="block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 27.2333px 7.91667px; transform-origin: 27.2333px 7.91667px; unicode-bidi: normal; ">th prime <img src="data:image/png;base64,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" alt="p_n" style="width: 15.5px; height: 20px;" width="15.5" height="20"><span style="block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 56.7833px 7.91667px; transform-origin: 56.7833px 7.91667px; unicode-bidi: normal; ">. For example, for n<span style="block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 143.75px 7.91667px; transform-origin: 143.75px 7.91667px; unicode-bidi: normal; "> = 12, the primorial is 7420738134810, whose last non-zero digit is 1.</div><div style="block-size: 21.25px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.6333px; text-align: left; transform-origin: 384px 10.6333px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; "><span style="block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 132.267px 7.91667px; transform-origin: 132.267px 7.91667px; unicode-bidi: normal; ">Find the last non-zero digit in the primorial <img src="data:image/png;base64,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" alt="p_n" style="width: 15.5px; height: 20px;" width="15.5" height="20"><span style="block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 5.83333px 7.91667px; transform-origin: 5.83333px 7.91667px; unicode-bidi: normal; ">#.</div><div style="block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; "><span style="block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 27.2333px 7.91667px; transform-origin: 27.2333px 7.91667px; unicode-bidi: normal; ">See also<span style="block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 1.95px 7.91667px; transform-origin: 1.95px 7.91667px; unicode-bidi: normal; "> <a target='_blank' href = "https://www.mathworks.com/matlabcentral/cody/problems/46054-count-trailing-zeros-in-a-primorial">Cody Problems 46054</a><span style="block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 124.783px 7.91667px; transform-origin: 124.783px 7.91667px; unicode-bidi: normal; "> "Count trailing zeros in a primorial" and <a target='_blank' href = "https://www.mathworks.com/matlabcentral/cody/problems/46060-identify-primorial-primes">46060 "Identify primorial primes"</a><span style="block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 1.95px 7.91667px; transform-origin: 1.95px 7.91667px; unicode-bidi: normal; ">.</div></div></div>

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Problem 46057. Find the last non-zero digit in a primorial

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Problem 46057. Find the last non-zero digit in a primorial

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